The present invention relates to an eccentric orbiting type driving apparatus which eccentrically orbits about a given shaft and eccentrically drives without any self-rotation.
A conventional eccentric orbiting type driving apparatus includes a converting mechanism for converting rotational motion into eccentric orbiting motion, which is connected to a motor.
However, such an eccentric orbiting type driving apparatus involves a complicated structure and a high manufacturing cost.
The present invention has been made to solve the above problem. It is therefore an object of the present invention to provide an eccentric orbiting type driving apparatus having a simple structure and a low manufacturing cost.
In order to achieve this object, according to the present invention, there is provided an eccentric orbiting type driving apparatus comprising a casing, a stator fixed to the casing, a rotary shaft rotatably supported by the casing, a rotor fixed to the rotary shaft, an orbiting shaft supported eccentrically and rotatably by the rotary shaft, and anti-self-rotation means for preventing the self-rotation of the orbiting shaft.
In the above eccentric orbiting type driving apparatus, the orbiting shaft may be mounted within the rotary shaft. The orbiting shaft may also be provided with an orbiting plate fixed to the upper or lower section of the orbiting shaft. Each of the rotary shaft and the orbiting shaft may be supported at two points. In addition, a seal means may be provided between the casing and the orbiting shaft. An upper end or both ends of the orbiting shaft may be protruded out of the casing. The anti-self-rotation means may include an Oldham""s ring.
Further, according to the present invention, there is provided an eccentric orbiting type driving apparatus comprising a casing, a stator fixed to the casing, a rotary shaft rotatably supported by the casing, a rotor fixed to the rotary shaft, an orbiting shaft supported eccentrically and rotatably by the rotary shaft, an orbiting plate fixed to the lower section of the orbiting shaft, and an anti-self-rotation means for preventing the self-rotation of the orbiting shaft, which is provided between the orbiting plate and the casing
Furthermore, according to the present invention, there is provided an eccentric orbiting type driving apparatus comprising a casing, a stator fixed to the casing, a bearing support fixed by the casing, a rotary shaft rotatably supported by the bearing support through a bearing, a rotor fixed to the rotary shaft, an orbiting shaft supported eccentrically and rotatably by the rotary shaft through a bearing and having an upper end protruding from the casing, an orbiting plate fixed to the lower section of the orbiting shaft, an Oldham""s Ling having a protrusion and provided between the bearing support and the orbiting plate, and grooves orthogonal to each other and provided in the bearing support and the orbiting plate, respectively, wherein the orthogonal grooves are engage with the protrusion to prevent the self-rotation of the orbiting shaft.